<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<script type="text/javascript" src="js/jquery.js" ></script>
		<script>
			function add(a, b) { return a + b; }

			function sub(a, b) { return a - b; }
			var a1 = sub.call(add, 4, 2);//2
			var a2 = sub.apply(add,[4,2]);
			var a3= add.call(sub, 4, 2);
			var a4= add.apply(sub, [5,6]);
		</script>
	</head>
	<body>
	</body>
</html>
